Key to the Practice Midterm

Problem 1:  Skip

Problem 2:  A.  y-int (1,15), x-int (-1,0), (5,0)

B.  -3(x - 2)² + 27

C.  Vertex:  (2,27) Concave down

Problem 3:  A.  (-infinity,-2)u(3,infinity)

B.  (-1.17,.233)u(1.14,infinity)

Problem 4:  Don't do

Problem 5:  A.  12.25 feet

B.  1.5 seconds

Problem 6: f(t) = 180t for 0 < t < 10,   1800 for 10 <  t  < 15,   1800t - 25,200 for 15 < t < 22.8

Domain:  (0,22.8),  Range:  (0,15840)

Where t is in minutes and f(t) is in feet.